The present invention relates to wire harness components, and more specifically, to a double-molded wire joint having an integrated fuse.
Industrial-scale solar energy plants often use wire harnesses to simplify the challenge of combining multiple solar panels. By way of example, a standard wire harness typically has a single trunk with many branches, with each branch having at least one connector that engages a solar panel. In this manner a fairly large number of solar panels can “feed” their photovoltaic power into a trunk. Multiple trunks typically feed into a combiner box. This is depicted in FIG. 1. Without wire harnesses each individual solar panel would need to individually feed into a combiner box, which would be a cumbersome and dangerous cluster of wires.
As shown in FIG. 2, a wire harness uses a variety of joints to form branches off a trunk, and to allow for multiple connectors on a single branch. Joints and wire harnesses are disclosed in U.S. Pat. No. 8,604,342 for LOW LEAKAGE ELECTRICAL JOINTS AND WIRE HARNESSES, AND METHOD OF MAKING THE SAME, which issued Dec. 10, 2013.
In early versions of wire harnesses each trunk would feed into a single fuse in the combiner box, as shown in FIG. 1. As a result, an issue with one panel could affect all panels in an array. In-line fuses, such as that depicted in FIG. 2, overcame this shortcoming. This improvement is disclosed in U.S. Pat. No. 8,937,249 for SOLAR ENERGY WIRE HARNESS WITH IN-LINE FUSES, which issued Jan. 20, 2015.
A shortcoming of integrating in-line fuses into a wire harness, however, is the number of connection points required. As shown in FIG. 3, a segment of a wire harness incorporating a joint, in-line fuse, and connector requires four separate connection points. Because electrical and mechanical failures are more likely to occur in connection points, and because connection points are less efficient conductors, it is desirable to have as few connection points as possible.
Another shortcoming of wire harnesses having in-line fuses is the exposed wire section downstream of the in-line fuse, before the joint. This weak area is identified by an electrical bolt in FIG. 3. Because this section is downstream of the in-line fuse, a short would cause massive harness failure before popping the fuse.
Yet another related improvement was integrating a fuse with the connector, as disclosed in application Ser. No. 14/295,132, for a PHOTOVOLTAIC IN LINE FUSE CONNECTOR ASSEMBLY HAVING AN INTEGRAL FUSE, which was filed Jun. 3, 2014. All references are hereby incorporated in their entirety.
What is lacking, however, is a joint that is integrated with a fuse, which would streamline wire harnesses, offer better protection from an electrical and mechanical point of view, and reduce the number of connection points thereby providing higher efficiency and reliability.